Time for the next update!
I'm with Nick Stanbury in not buying the idea of a 'London Flap' being provided to put planks between wagons. My first question would be: why should anyone want to put planks across in the first place? The only place where sidings were close together was where wagons were stabled - they had to have a reasonable interval between them to allow unloading unless bottom discharge was used and if anyone wanted to know what was in a wagon they need only look at the label - on the solebar.
So maybe planks were used to make shortcuts across sidings in the way suggested by that hardly lends itself as a reason for constructing a wagon in a particular way. I have also done a spot of delving back in rule books and, while lots of things are mentioned before shunting commences, there is no mention of planks between wagons - which suggests that, if it did happen, it was very unofficial and sufficiently uncommon to have never resulted in an accident. So, I too will be interested to hear more.
Mike Romans
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At last, a definitive answer to the reason for 'London Trader's Top Flaps' on 16-ton steel mineral wagons, or is it?
Quote from Hansard for 18 December 1947:
"Mr Sharp asked the Minister of Transport what is the additional cost and weight of the 16 tons steel mineral wagon caused by the provision of top flap door now required by his Department; and why this is now deemed essential.
Mr Barnes replied that the additional cost is £6 a wagon and the extra weight 1 cwt. The doors are being fitted at the request of the Chamber of Coal Traders in order to reduce strain on men engaged in unloading."
So how did they reduce strain? I note that these top flaps were fitted to the BR 16T, 21T and 24.5T steel wagons and earlier variants. In the case of the 21T, the first series produced around 1950 did not have the flaps. There was a second series designed in 1961 and produced until 1963. The second series had vacuum brakes, roller bearings and...top flaps. The 24.5 tonner, at 9 feet 10 inches high, was taller than the other wagons. It had top flaps, and these are much larger than on the other two wagons. This was because the size of the side door, and the reinforcing bar above it, seems to be in more or less the same position as the smaller capacity wagons.
There is a photograph of the 24.5T wagon here
http://gallery6801.fotopic.net/p3171461.html which can be compared to the 16T at
http://gallery6801.fotopic.net/p52653360.html.
Photographs of these wagons being unloaded show that the flap is at about head level, and this I think is the clue to what the top flap doors were for. They were there so that once they could be dropped, a person standing in the wagon could then see out without stooping to look out from under the side door, or by standing on the load. This idea is reinforced by the existence of a 1965 report which noted that coal wagons were being delivered to around 20,000 coal merchants at that time, and that most were small organisations where the normal method of unloading was by hand with two man teams. Hand unloading of wagons declined after the mid-1960s with the introduction of coal concentration depots, and the decline in the use of coal as a domestic fuel. British railways started to re-body its steel mineral wagon fleet from the 1970s onward, and none of the re-bodied wagons included the top flaps.
Colin Hume
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Re unloading coal, I use to do this once a month when I was lampman in the Shirebrook area. At that time, we had 17 signal boxes to cover for lamping. What we use to do was drop main door then throw coal out, I could work from both left and right sides of the door.
Kevin Mulhall